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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Copyright (C) 2010 TTPASI, Inc. All Rights Reserved.<a name="line.2"></a>
<FONT color="green">003</FONT>     *<a name="line.3"></a>
<FONT color="green">004</FONT>     * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<FONT color="green">005</FONT>     * you may not use this file except in compliance with the License.<a name="line.5"></a>
<FONT color="green">006</FONT>     * You may obtain a copy of the License at<a name="line.6"></a>
<FONT color="green">007</FONT>     *<a name="line.7"></a>
<FONT color="green">008</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<FONT color="green">009</FONT>     *<a name="line.9"></a>
<FONT color="green">010</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<FONT color="green">011</FONT>     * distributed under the License is distributed on an "AS-IS" BASIS,<a name="line.11"></a>
<FONT color="green">012</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<FONT color="green">013</FONT>     * See the License for the specific language governing permissions and<a name="line.13"></a>
<FONT color="green">014</FONT>     * limitations under the License.<a name="line.14"></a>
<FONT color="green">015</FONT>     */<a name="line.15"></a>
<FONT color="green">016</FONT>    <a name="line.16"></a>
<FONT color="green">017</FONT>    package ttpasi.jgenere.initial_port;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import static ttpasi.jgenere.initial_port.Utils.isAlpha;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    import java.util.ArrayList;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.util.Collections;<a name="line.22"></a>
<FONT color="green">023</FONT>    import java.util.HashMap;<a name="line.23"></a>
<FONT color="green">024</FONT>    import java.util.List;<a name="line.24"></a>
<FONT color="green">025</FONT>    import java.util.Map;<a name="line.25"></a>
<FONT color="green">026</FONT>    <a name="line.26"></a>
<FONT color="green">027</FONT>    import ttpasi.jgenere.initial_port.languagedata.LanguageData;<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>    <a name="line.29"></a>
<FONT color="green">030</FONT>    /**<a name="line.30"></a>
<FONT color="green">031</FONT>     * Java port of VigCrack from PyGenere v 0.3.  See pygenere.py to learn more <a name="line.31"></a>
<FONT color="green">032</FONT>     * about the original PyGenere implementation, including author contact <a name="line.32"></a>
<FONT color="green">033</FONT>     * information and licensing and use terms.<a name="line.33"></a>
<FONT color="green">034</FONT>     * &lt;p/&gt;<a name="line.34"></a>
<FONT color="green">035</FONT>     * VigCrack objects can crack some cipher keys and messages of Vigenere <a name="line.35"></a>
<FONT color="green">036</FONT>     * enciphered messages.  Longer messages are more likely crackable by this <a name="line.36"></a>
<FONT color="green">037</FONT>     * algorithm than shorter messages.<a name="line.37"></a>
<FONT color="green">038</FONT>     * &lt;p/&gt;<a name="line.38"></a>
<FONT color="green">039</FONT>     * VigCrack objects are immutable.<a name="line.39"></a>
<FONT color="green">040</FONT>     * &lt;p/&gt;<a name="line.40"></a>
<FONT color="green">041</FONT>     * Note: This implementation only supports characters in the English alphabet, <a name="line.41"></a>
<FONT color="green">042</FONT>     * though multiple languages are supported.<a name="line.42"></a>
<FONT color="green">043</FONT>     * &lt;p/&gt;<a name="line.43"></a>
<FONT color="green">044</FONT>     * This typical use sequence cracks a Vigenere encryption key <a name="line.44"></a>
<FONT color="green">045</FONT>     * &lt;pre&gt;<a name="line.45"></a>
<FONT color="green">046</FONT>     * VigCrack vc = new VigCrack(_codedtext);<a name="line.46"></a>
<FONT color="green">047</FONT>     * String codeword = vc.crackCodeword(new String[] {"5", "9"});<a name="line.47"></a>
<FONT color="green">048</FONT>     * &lt;/pre&gt;<a name="line.48"></a>
<FONT color="green">049</FONT>     * This typical use sequence cracks a Vigenere encryption key and decrypts the <a name="line.49"></a>
<FONT color="green">050</FONT>     * encrypted message<a name="line.50"></a>
<FONT color="green">051</FONT>     * &lt;pre&gt;<a name="line.51"></a>
<FONT color="green">052</FONT>     * VigCrack vc = new VigCrack(_codedtext);<a name="line.52"></a>
<FONT color="green">053</FONT>     * String message = vc.crackMessage(new String[] {"5", "9"});<a name="line.53"></a>
<FONT color="green">054</FONT>     * &lt;/pre&gt;<a name="line.54"></a>
<FONT color="green">055</FONT>     * See jgenere.initial_port.VigCrackTest source code for further example uses, <a name="line.55"></a>
<FONT color="green">056</FONT>     * including how to use VigCrack with different languages.<a name="line.56"></a>
<FONT color="green">057</FONT>     * &lt;p/&gt;<a name="line.57"></a>
<FONT color="green">058</FONT>     * Note: While the cryptography implementations in jgenere.initial_port work <a name="line.58"></a>
<FONT color="green">059</FONT>     * correctly according to the provided test cases, they were not optimized or <a name="line.59"></a>
<FONT color="green">060</FONT>     * otherwise designed to make use of Java language and platform features.  They <a name="line.60"></a>
<FONT color="green">061</FONT>     * are simple ports of the original Python implementation of PyGenere, provided <a name="line.61"></a>
<FONT color="green">062</FONT>     * for academic purposes.  Visit the project web site at <a name="line.62"></a>
<FONT color="green">063</FONT>     * &lt;a target="_blank" href="http://code.google.com/p/jgenere/"&gt;http://code.google.com/p/jgenere/&lt;/a&gt; <a name="line.63"></a>
<FONT color="green">064</FONT>     * for preferred Java-based implementations of these cryptography algorithms.<a name="line.64"></a>
<FONT color="green">065</FONT>     * &lt;p/&gt;<a name="line.65"></a>
<FONT color="green">066</FONT>     * The original PyGenere v 0.3 VigCrack code:<a name="line.66"></a>
<FONT color="green">067</FONT>     * &lt;pre&gt;<a name="line.67"></a>
<FONT color="green">068</FONT>     * class VigCrack(Vigenere):<a name="line.68"></a>
<FONT color="green">069</FONT>     * <a name="line.69"></a>
<FONT color="green">070</FONT>     *   """<a name="line.70"></a>
<FONT color="green">071</FONT>     *   VigCrack objects have methods to break Vigenere-encoded texts when the<a name="line.71"></a>
<FONT color="green">072</FONT>     *   original key is unknown.<a name="line.72"></a>
<FONT color="green">073</FONT>     * <a name="line.73"></a>
<FONT color="green">074</FONT>     *   The technique used is based on the one described in:<a name="line.74"></a>
<FONT color="green">075</FONT>     * <a name="line.75"></a>
<FONT color="green">076</FONT>     *   http: * www.stonehill.edu/compsci/Shai_papers/RSA.pdf<a name="line.76"></a>
<FONT color="green">077</FONT>     *   (pages 9-10)<a name="line.77"></a>
<FONT color="green">078</FONT>     * <a name="line.78"></a>
<FONT color="green">079</FONT>     *   Character frequencies taken from:<a name="line.79"></a>
<FONT color="green">080</FONT>     *   http: * www.csm.astate.edu/~rossa/datasec/frequency.html (English)<a name="line.80"></a>
<FONT color="green">081</FONT>     *   http: * www.characterfrequency.com/ (French, Italian, Portuguese, Spanish)<a name="line.81"></a>
<FONT color="green">082</FONT>     *   http: * www.santacruzpl.org/readyref/files/g-l/ltfrqger.shtml (German)<a name="line.82"></a>
<FONT color="green">083</FONT>     *   """<a name="line.83"></a>
<FONT color="green">084</FONT>     * <a name="line.84"></a>
<FONT color="green">085</FONT>     *   # Unless otherwise specified, test for codewords between (and including)<a name="line.85"></a>
<FONT color="green">086</FONT>     *   # these two lengths:<a name="line.86"></a>
<FONT color="green">087</FONT>     *   __default_min_codeword_length = 5<a name="line.87"></a>
<FONT color="green">088</FONT>     *   __default_max_codeword_length = 9<a name="line.88"></a>
<FONT color="green">089</FONT>     * <a name="line.89"></a>
<FONT color="green">090</FONT>     *   # The following are language-specific data on character frequencies.<a name="line.90"></a>
<FONT color="green">091</FONT>     *   # Kappa is the "index of coincidence" described in the cryptography paper<a name="line.91"></a>
<FONT color="green">092</FONT>     *   # (link above).<a name="line.92"></a>
<FONT color="green">093</FONT>     *   __english_data = {<a name="line.93"></a>
<FONT color="green">094</FONT>     *                     'A':8.167, 'B':1.492, 'C':2.782, 'D':4.253, 'E':12.702,<a name="line.94"></a>
<FONT color="green">095</FONT>     *                     'F':2.228, 'G':2.015, 'H':6.094, 'I':6.996, 'J':0.153,<a name="line.95"></a>
<FONT color="green">096</FONT>     *                     'K':0.772, 'L':4.025, 'M':2.406, 'N':6.749, 'O':7.507,<a name="line.96"></a>
<FONT color="green">097</FONT>     *                     'P':1.929, 'Q':0.095, 'R':5.987, 'S':6.327, 'T':9.056,<a name="line.97"></a>
<FONT color="green">098</FONT>     *                     'U':2.758, 'V':0.978, 'W':2.360, 'X':0.150, 'Y':1.974,<a name="line.98"></a>
<FONT color="green">099</FONT>     *                     'Z':0.074, 'max_val':12.702, 'kappa':0.0667<a name="line.99"></a>
<FONT color="green">100</FONT>     *                    }<a name="line.100"></a>
<FONT color="green">101</FONT>     * <a name="line.101"></a>
<FONT color="green">102</FONT>     *   __french_data = {<a name="line.102"></a>
<FONT color="green">103</FONT>     *                    'A':8.11, 'B':0.903, 'C':3.49, 'D':4.27, 'E':17.22,<a name="line.103"></a>
<FONT color="green">104</FONT>     *                    'F':1.14, 'G':1.09, 'H':0.769, 'I':7.44, 'J':0.339,<a name="line.104"></a>
<FONT color="green">105</FONT>     *                    'K':0.097, 'L':5.53, 'M':2.89, 'N':7.46, 'O':5.38,<a name="line.105"></a>
<FONT color="green">106</FONT>     *                    'P':3.02, 'Q':0.999, 'R':7.05, 'S':8.04, 'T':6.99,<a name="line.106"></a>
<FONT color="green">107</FONT>     *                    'U':5.65, 'V':1.30, 'W':0.039, 'X':0.435, 'Y':0.271,<a name="line.107"></a>
<FONT color="green">108</FONT>     *                    'Z':0.098, 'max_val':17.22, 'kappa':0.0746<a name="line.108"></a>
<FONT color="green">109</FONT>     *                   }<a name="line.109"></a>
<FONT color="green">110</FONT>     * <a name="line.110"></a>
<FONT color="green">111</FONT>     *   __german_data = {<a name="line.111"></a>
<FONT color="green">112</FONT>     *                    'A':6.506, 'B':2.566, 'C':2.837, 'D':5.414, 'E':16.693,<a name="line.112"></a>
<FONT color="green">113</FONT>     *                    'F':2.044, 'G':3.647, 'H':4.064, 'I':7.812, 'J':0.191,<a name="line.113"></a>
<FONT color="green">114</FONT>     *                    'K':1.879, 'L':2.825, 'M':3.005, 'N':9.905, 'O':2.285,<a name="line.114"></a>
<FONT color="green">115</FONT>     *                    'P':0.944, 'Q':0.055, 'R':6.539, 'S':6.765, 'T':6.742,<a name="line.115"></a>
<FONT color="green">116</FONT>     *                    'U':3.703, 'V':1.069, 'W':1.396, 'X':0.022, 'Y':0.032,<a name="line.116"></a>
<FONT color="green">117</FONT>     *                    'Z':1.002, 'max_val':16.693, 'kappa':0.0767<a name="line.117"></a>
<FONT color="green">118</FONT>     *                   }<a name="line.118"></a>
<FONT color="green">119</FONT>     * <a name="line.119"></a>
<FONT color="green">120</FONT>     *   __italian_data = {<a name="line.120"></a>
<FONT color="green">121</FONT>     *                     'A':11.30, 'B':0.975, 'C':4.35, 'D':3.80, 'E':11.24,<a name="line.121"></a>
<FONT color="green">122</FONT>     *                     'F':1.09, 'G':1.73, 'H':1.02, 'I':11.57, 'J':0.035,<a name="line.122"></a>
<FONT color="green">123</FONT>     *                     'K':0.078, 'L':6.40, 'M':2.66, 'N':7.29, 'O':9.11,<a name="line.123"></a>
<FONT color="green">124</FONT>     *                     'P':2.89, 'Q':0.391, 'R':6.68, 'S':5.11, 'T':6.76,<a name="line.124"></a>
<FONT color="green">125</FONT>     *                     'U':3.18, 'V':1.52, 'W':0.00, 'X':0.024, 'Y':0.048,<a name="line.125"></a>
<FONT color="green">126</FONT>     *                     'Z':0.958, 'max_val':11.57, 'kappa':0.0733<a name="line.126"></a>
<FONT color="green">127</FONT>     *                    }<a name="line.127"></a>
<FONT color="green">128</FONT>     * <a name="line.128"></a>
<FONT color="green">129</FONT>     *   __portuguese_data = {<a name="line.129"></a>
<FONT color="green">130</FONT>     *                        'A':13.89, 'B':0.980, 'C':4.18, 'D':5.24, 'E':12.72,<a name="line.130"></a>
<FONT color="green">131</FONT>     *                        'F':1.01, 'G':1.17, 'H':0.905, 'I':6.70, 'J':0.317,<a name="line.131"></a>
<FONT color="green">132</FONT>     *                        'K':0.0174, 'L':2.76, 'M':4.54, 'N':5.37, 'O':10.90,<a name="line.132"></a>
<FONT color="green">133</FONT>     *                        'P':2.74, 'Q':1.06, 'R':6.67, 'S':7.90, 'T':4.63,<a name="line.133"></a>
<FONT color="green">134</FONT>     *                        'U':4.05, 'V':1.55, 'W':0.0104, 'X':0.272, 'Y':0.0165,<a name="line.134"></a>
<FONT color="green">135</FONT>     *                        'Z':0.400, 'max_val':13.89, 'kappa':0.0745<a name="line.135"></a>
<FONT color="green">136</FONT>     *                       }<a name="line.136"></a>
<FONT color="green">137</FONT>     * <a name="line.137"></a>
<FONT color="green">138</FONT>     *   __spanish_data = {<a name="line.138"></a>
<FONT color="green">139</FONT>     *                     'A':12.09, 'B':1.21, 'C':4.20, 'D':4.65, 'E':13.89,<a name="line.139"></a>
<FONT color="green">140</FONT>     *                     'F':0.642, 'G':1.11, 'H':1.13, 'I':6.38, 'J':0.461,<a name="line.140"></a>
<FONT color="green">141</FONT>     *                     'K':0.038, 'L':5.19, 'M':2.86, 'N':7.23, 'O':9.58,<a name="line.141"></a>
<FONT color="green">142</FONT>     *                     'P':2.74, 'Q':1.37, 'R':6.14, 'S':7.43, 'T':4.49,<a name="line.142"></a>
<FONT color="green">143</FONT>     *                     'U':4.53, 'V':1.05, 'W':0.011, 'X':0.124, 'Y':1.14,<a name="line.143"></a>
<FONT color="green">144</FONT>     *                     'Z':0.324, 'max_val':13.89, 'kappa':0.0766<a name="line.144"></a>
<FONT color="green">145</FONT>     *                    }<a name="line.145"></a>
<FONT color="green">146</FONT>     * <a name="line.146"></a>
<FONT color="green">147</FONT>     *   # The default language is set to English.<a name="line.147"></a>
<FONT color="green">148</FONT>     *   __lang = 'EN'<a name="line.148"></a>
<FONT color="green">149</FONT>     *   __lang_data = __english_data<a name="line.149"></a>
<FONT color="green">150</FONT>     * <a name="line.150"></a>
<FONT color="green">151</FONT>     *   # This method sets the lang (__lang) attribute of a VigCrack object.<a name="line.151"></a>
<FONT color="green">152</FONT>     *   def set_language(self, language):<a name="line.152"></a>
<FONT color="green">153</FONT>     *       self.__lang = language.upper()<a name="line.153"></a>
<FONT color="green">154</FONT>     *       if self.__lang == 'DE':<a name="line.154"></a>
<FONT color="green">155</FONT>     *           self.__lang_data = self.__german_data<a name="line.155"></a>
<FONT color="green">156</FONT>     *       elif self.__lang == 'ES':<a name="line.156"></a>
<FONT color="green">157</FONT>     *           self.__lang_data = self.__spanish_data<a name="line.157"></a>
<FONT color="green">158</FONT>     *       elif self.__lang == 'FR':<a name="line.158"></a>
<FONT color="green">159</FONT>     *           self.__lang_data = self.__french_data<a name="line.159"></a>
<FONT color="green">160</FONT>     *       elif self.__lang == 'IT':<a name="line.160"></a>
<FONT color="green">161</FONT>     *           self.__lang_data = self.__italian_data<a name="line.161"></a>
<FONT color="green">162</FONT>     *       elif self.__lang == 'PT':<a name="line.162"></a>
<FONT color="green">163</FONT>     *           self.__lang_data = self.__portuguese_data<a name="line.163"></a>
<FONT color="green">164</FONT>     *       else:<a name="line.164"></a>
<FONT color="green">165</FONT>     *           self.__lang = 'EN'<a name="line.165"></a>
<FONT color="green">166</FONT>     *       return self<a name="line.166"></a>
<FONT color="green">167</FONT>     * <a name="line.167"></a>
<FONT color="green">168</FONT>     *   # Rotate text n places to the right, wrapping around at the end.<a name="line.168"></a>
<FONT color="green">169</FONT>     *   def __rotate_right(self, n):<a name="line.169"></a>
<FONT color="green">170</FONT>     *       cutting_point = len(self) - (n % len(self))<a name="line.170"></a>
<FONT color="green">171</FONT>     *       return self[cutting_point:] + self[:cutting_point]<a name="line.171"></a>
<FONT color="green">172</FONT>     * <a name="line.172"></a>
<FONT color="green">173</FONT>     *   # Get every nth char from a piece of text, from a given starting position.<a name="line.173"></a>
<FONT color="green">174</FONT>     *   def __get_every_nth_char(self, start, n):<a name="line.174"></a>
<FONT color="green">175</FONT>     *       accumulator = []<a name="line.175"></a>
<FONT color="green">176</FONT>     *       for i in range(len(self)):<a name="line.176"></a>
<FONT color="green">177</FONT>     *           if (i % n) == start:<a name="line.177"></a>
<FONT color="green">178</FONT>     *               accumulator.append(self[i])<a name="line.178"></a>
<FONT color="green">179</FONT>     *       return VigCrack(''.join(accumulator)).set_language(self.__lang)<a name="line.179"></a>
<FONT color="green">180</FONT>     * <a name="line.180"></a>
<FONT color="green">181</FONT>     *   # Build a dictionary containing the number of occurrences of each char.<a name="line.181"></a>
<FONT color="green">182</FONT>     *   def __count_char_freqs(self):<a name="line.182"></a>
<FONT color="green">183</FONT>     *       dictionary = {}<a name="line.183"></a>
<FONT color="green">184</FONT>     *       self = self.upper()<a name="line.184"></a>
<FONT color="green">185</FONT>     *       for char in self:<a name="line.185"></a>
<FONT color="green">186</FONT>     *           if char.isalpha():<a name="line.186"></a>
<FONT color="green">187</FONT>     *               dictionary[char] = dictionary.get(char, 0) + 1<a name="line.187"></a>
<FONT color="green">188</FONT>     *       return dictionary<a name="line.188"></a>
<FONT color="green">189</FONT>     * <a name="line.189"></a>
<FONT color="green">190</FONT>     *   # Scale the dictionary so that it can be compared with __lang_data.<a name="line.190"></a>
<FONT color="green">191</FONT>     *   def __scale(self, dictionary):<a name="line.191"></a>
<FONT color="green">192</FONT>     *       v = dictionary.values()<a name="line.192"></a>
<FONT color="green">193</FONT>     *       v.sort()<a name="line.193"></a>
<FONT color="green">194</FONT>     *       max_val = v[-1]<a name="line.194"></a>
<FONT color="green">195</FONT>     *       scaling_factor = self.__lang_data['max_val']/max_val<a name="line.195"></a>
<FONT color="green">196</FONT>     *       for (k, v) in dictionary.items():<a name="line.196"></a>
<FONT color="green">197</FONT>     *           dictionary[k] = v*scaling_factor<a name="line.197"></a>
<FONT color="green">198</FONT>     *       return dictionary<a name="line.198"></a>
<FONT color="green">199</FONT>     * <a name="line.199"></a>
<FONT color="green">200</FONT>     *   # The residual error is the difference between a char's frequency in<a name="line.200"></a>
<FONT color="green">201</FONT>     *   # __lang_data and its frequency in the scaled dictionary from above.<a name="line.201"></a>
<FONT color="green">202</FONT>     *   # The error is then squared to remove a possible negative value.<a name="line.202"></a>
<FONT color="green">203</FONT>     *   def __sum_residuals_squared(self, dictionary):<a name="line.203"></a>
<FONT color="green">204</FONT>     *       sum = 0<a name="line.204"></a>
<FONT color="green">205</FONT>     *       for (k, v) in dictionary.items():<a name="line.205"></a>
<FONT color="green">206</FONT>     *           sum += (v - self.__lang_data[k])**2<a name="line.206"></a>
<FONT color="green">207</FONT>     *       return sum<a name="line.207"></a>
<FONT color="green">208</FONT>     * <a name="line.208"></a>
<FONT color="green">209</FONT>     *   # Find the Caesar shift that brings the ciphertext closest to the<a name="line.209"></a>
<FONT color="green">210</FONT>     *   # character distribution of the plaintext's language.<a name="line.210"></a>
<FONT color="green">211</FONT>     *   def __find_best_caesar_shift(self):<a name="line.211"></a>
<FONT color="green">212</FONT>     *       best = 0<a name="line.212"></a>
<FONT color="green">213</FONT>     *       smallest_sum = -1<a name="line.213"></a>
<FONT color="green">214</FONT>     *       # Find the residual sum for each shift.<a name="line.214"></a>
<FONT color="green">215</FONT>     *       for shift in range(26):<a name="line.215"></a>
<FONT color="green">216</FONT>     *           encoded_text = Caesar(self).encipher(shift)<a name="line.216"></a>
<FONT color="green">217</FONT>     *           vigcrack_obj = VigCrack(encoded_text).set_language(self.__lang)<a name="line.217"></a>
<FONT color="green">218</FONT>     *           char_freqs = vigcrack_obj.__count_char_freqs()<a name="line.218"></a>
<FONT color="green">219</FONT>     *           scaled = vigcrack_obj.__scale(char_freqs)<a name="line.219"></a>
<FONT color="green">220</FONT>     *           current_sum = vigcrack_obj.__sum_residuals_squared(scaled)<a name="line.220"></a>
<FONT color="green">221</FONT>     *           # Keep track of the shift with the lowest residual sum.<a name="line.221"></a>
<FONT color="green">222</FONT>     *           # If there's a tie, the smallest shift wins.<a name="line.222"></a>
<FONT color="green">223</FONT>     *           if smallest_sum == -1:<a name="line.223"></a>
<FONT color="green">224</FONT>     *               smallest_sum = current_sum<a name="line.224"></a>
<FONT color="green">225</FONT>     *           if current_sum &lt; smallest_sum:<a name="line.225"></a>
<FONT color="green">226</FONT>     *               best = shift<a name="line.226"></a>
<FONT color="green">227</FONT>     *               smallest_sum = current_sum<a name="line.227"></a>
<FONT color="green">228</FONT>     *       return best<a name="line.228"></a>
<FONT color="green">229</FONT>     * <a name="line.229"></a>
<FONT color="green">230</FONT>     *   def __find_codeword_length(self, min_length, max_length):<a name="line.230"></a>
<FONT color="green">231</FONT>     *       codeword_length = min_length<a name="line.231"></a>
<FONT color="green">232</FONT>     *       kappas = []<a name="line.232"></a>
<FONT color="green">233</FONT>     *       # Put the kappa value for each codeword length tested into an array.<a name="line.233"></a>
<FONT color="green">234</FONT>     *       for i in range(min_length, max_length + 1):<a name="line.234"></a>
<FONT color="green">235</FONT>     *           temp = self.__rotate_right(i)<a name="line.235"></a>
<FONT color="green">236</FONT>     *           coincidences = 0<a name="line.236"></a>
<FONT color="green">237</FONT>     *           for j in range(len(self)):<a name="line.237"></a>
<FONT color="green">238</FONT>     *               if temp[j] == self[j]:<a name="line.238"></a>
<FONT color="green">239</FONT>     *                   coincidences += 1<a name="line.239"></a>
<FONT color="green">240</FONT>     *           kappas.append(float(coincidences)/len(self))<a name="line.240"></a>
<FONT color="green">241</FONT>     *       # Find out which value of kappa is closest to the kappa of the<a name="line.241"></a>
<FONT color="green">242</FONT>     *       # plaintext's language.  If there's a tie, the shortest codeword wins.<a name="line.242"></a>
<FONT color="green">243</FONT>     *       smallest_squared_diff = -1<a name="line.243"></a>
<FONT color="green">244</FONT>     *       for i in range((max_length + 1) - min_length):<a name="line.244"></a>
<FONT color="green">245</FONT>     *           current_squared_diff = (self.__lang_data['kappa'] - kappas[i])**2<a name="line.245"></a>
<FONT color="green">246</FONT>     *           if smallest_squared_diff == -1:<a name="line.246"></a>
<FONT color="green">247</FONT>     *               smallest_squared_diff = current_squared_diff<a name="line.247"></a>
<FONT color="green">248</FONT>     *           if current_squared_diff &lt; smallest_squared_diff:<a name="line.248"></a>
<FONT color="green">249</FONT>     *               codeword_length = min_length + i<a name="line.249"></a>
<FONT color="green">250</FONT>     *               smallest_squared_diff = current_squared_diff<a name="line.250"></a>
<FONT color="green">251</FONT>     *       return codeword_length<a name="line.251"></a>
<FONT color="green">252</FONT>     * <a name="line.252"></a>
<FONT color="green">253</FONT>     *   def __find_codeword(self, min_length, max_length):<a name="line.253"></a>
<FONT color="green">254</FONT>     *       # Strip away invalid chars.<a name="line.254"></a>
<FONT color="green">255</FONT>     *       accumulator = []<a name="line.255"></a>
<FONT color="green">256</FONT>     *       for char in self:<a name="line.256"></a>
<FONT color="green">257</FONT>     *           if char.isalpha():<a name="line.257"></a>
<FONT color="green">258</FONT>     *               accumulator.append(char)<a name="line.258"></a>
<FONT color="green">259</FONT>     *       alpha_only = VigCrack(''.join(accumulator)).set_language(self.__lang)<a name="line.259"></a>
<FONT color="green">260</FONT>     *       codeword_length = alpha_only.__find_codeword_length(min_length,<a name="line.260"></a>
<FONT color="green">261</FONT>     *                                                           max_length)<a name="line.261"></a>
<FONT color="green">262</FONT>     *       # Build the codeword by finding one character at a time.<a name="line.262"></a>
<FONT color="green">263</FONT>     *       codeword = []<a name="line.263"></a>
<FONT color="green">264</FONT>     *       for i in range(codeword_length):<a name="line.264"></a>
<FONT color="green">265</FONT>     *           temp = alpha_only.__get_every_nth_char(i, codeword_length)<a name="line.265"></a>
<FONT color="green">266</FONT>     *           shift = temp.__find_best_caesar_shift()<a name="line.266"></a>
<FONT color="green">267</FONT>     *           if shift == 0:<a name="line.267"></a>
<FONT color="green">268</FONT>     *               codeword.append('A')<a name="line.268"></a>
<FONT color="green">269</FONT>     *           else:<a name="line.269"></a>
<FONT color="green">270</FONT>     *               codeword.append(chr(ord('A') + (26 - shift)))<a name="line.270"></a>
<FONT color="green">271</FONT>     *       return VigCrack(''.join(codeword)).set_language(self.__lang)<a name="line.271"></a>
<FONT color="green">272</FONT>     * <a name="line.272"></a>
<FONT color="green">273</FONT>     *   def __parse_args(self, *arg_list):<a name="line.273"></a>
<FONT color="green">274</FONT>     *       if len(arg_list) == 0:    # Use default values for codeword length.<a name="line.274"></a>
<FONT color="green">275</FONT>     *           min_length = self.__default_min_codeword_length<a name="line.275"></a>
<FONT color="green">276</FONT>     *           max_length = self.__default_max_codeword_length<a name="line.276"></a>
<FONT color="green">277</FONT>     *       elif len(arg_list) == 1:    # Exact codeword length specified by user.<a name="line.277"></a>
<FONT color="green">278</FONT>     *           min_length = max_length = int(arg_list[0])<a name="line.278"></a>
<FONT color="green">279</FONT>     *       else:    # min_length and max_length given by user.<a name="line.279"></a>
<FONT color="green">280</FONT>     *           min_length = int(arg_list[0])<a name="line.280"></a>
<FONT color="green">281</FONT>     *           max_length = int(arg_list[1])<a name="line.281"></a>
<FONT color="green">282</FONT>     *       # Check for input errors.<a name="line.282"></a>
<FONT color="green">283</FONT>     *       if min_length == max_length:<a name="line.283"></a>
<FONT color="green">284</FONT>     *           if min_length &lt; 1:<a name="line.284"></a>
<FONT color="green">285</FONT>     *               raise InputError('Codeword length is too small')<a name="line.285"></a>
<FONT color="green">286</FONT>     *       else:<a name="line.286"></a>
<FONT color="green">287</FONT>     *           if min_length &lt; 1:<a name="line.287"></a>
<FONT color="green">288</FONT>     *               raise InputError('min_length is too small')<a name="line.288"></a>
<FONT color="green">289</FONT>     *           if max_length &lt; 1:<a name="line.289"></a>
<FONT color="green">290</FONT>     *               raise InputError('max_length is too small')<a name="line.290"></a>
<FONT color="green">291</FONT>     *       if max_length &lt; min_length:<a name="line.291"></a>
<FONT color="green">292</FONT>     *           raise InputError('max_length cannot be shorter than min_length')<a name="line.292"></a>
<FONT color="green">293</FONT>     *       if len(self) == 0:<a name="line.293"></a>
<FONT color="green">294</FONT>     *           raise InputError('Ciphertext is empty')<a name="line.294"></a>
<FONT color="green">295</FONT>     *       if len(self) &lt; max_length:<a name="line.295"></a>
<FONT color="green">296</FONT>     *           raise InputError('Ciphertext is too short')<a name="line.296"></a>
<FONT color="green">297</FONT>     *       # Check that the ciphertext contains at least one valid character.<a name="line.297"></a>
<FONT color="green">298</FONT>     *       has_valid_char = False<a name="line.298"></a>
<FONT color="green">299</FONT>     *       for char in self:<a name="line.299"></a>
<FONT color="green">300</FONT>     *           if char.isalpha():<a name="line.300"></a>
<FONT color="green">301</FONT>     *               has_valid_char = True<a name="line.301"></a>
<FONT color="green">302</FONT>     *               break<a name="line.302"></a>
<FONT color="green">303</FONT>     *       if not has_valid_char:<a name="line.303"></a>
<FONT color="green">304</FONT>     *           raise InputError('No valid characters in ciphertext')<a name="line.304"></a>
<FONT color="green">305</FONT>     *       # If everything's all right, return the min_length and max_length.<a name="line.305"></a>
<FONT color="green">306</FONT>     *       return [min_length, max_length]<a name="line.306"></a>
<FONT color="green">307</FONT>     * <a name="line.307"></a>
<FONT color="green">308</FONT>     *   def crack_codeword(self, *arg_list):<a name="line.308"></a>
<FONT color="green">309</FONT>     *       """<a name="line.309"></a>
<FONT color="green">310</FONT>     *       Try to find the codeword that encrypted the ciphertext object.<a name="line.310"></a>
<FONT color="green">311</FONT>     *       If no arguments are supplied, codewords between the default minimum<a name="line.311"></a>
<FONT color="green">312</FONT>     *       length and the default maximum length are tried.<a name="line.312"></a>
<FONT color="green">313</FONT>     *       If one integer argument is supplied, only codewords with that length<a name="line.313"></a>
<FONT color="green">314</FONT>     *       will be tried.<a name="line.314"></a>
<FONT color="green">315</FONT>     *       If two integer arguments are given then the first argument is treated<a name="line.315"></a>
<FONT color="green">316</FONT>     *       as a minimum codeword length, and the second argument is treated as a<a name="line.316"></a>
<FONT color="green">317</FONT>     *       maximum codeword length, to try.<a name="line.317"></a>
<FONT color="green">318</FONT>     *       """<a name="line.318"></a>
<FONT color="green">319</FONT>     *       array = self.__parse_args(*arg_list)<a name="line.319"></a>
<FONT color="green">320</FONT>     *       return self.__find_codeword(array[0], array[1])<a name="line.320"></a>
<FONT color="green">321</FONT>     * <a name="line.321"></a>
<FONT color="green">322</FONT>     *   def crack_message(self, *arg_list):<a name="line.322"></a>
<FONT color="green">323</FONT>     *       """<a name="line.323"></a>
<FONT color="green">324</FONT>     *       Try to decode the ciphertext object.<a name="line.324"></a>
<FONT color="green">325</FONT>     *       This method accepts arguments in the same way as the crack_codeword()<a name="line.325"></a>
<FONT color="green">326</FONT>     *       method.<a name="line.326"></a>
<FONT color="green">327</FONT>     *       """<a name="line.327"></a>
<FONT color="green">328</FONT>     *       codeword = self.crack_codeword(*arg_list)<a name="line.328"></a>
<FONT color="green">329</FONT>     *       return self.decipher(codeword)<a name="line.329"></a>
<FONT color="green">330</FONT>     * &lt;/pre&gt;<a name="line.330"></a>
<FONT color="green">331</FONT>     * <a name="line.331"></a>
<FONT color="green">332</FONT>     * @author  Bruce [com.gmail @ ProgrammerBruce]<a name="line.332"></a>
<FONT color="green">333</FONT>     * @version 2010.1105<a name="line.333"></a>
<FONT color="green">334</FONT>     */<a name="line.334"></a>
<FONT color="green">335</FONT>    //class VigCrack(Vigenere):<a name="line.335"></a>
<FONT color="green">336</FONT>    public class VigCrack<a name="line.336"></a>
<FONT color="green">337</FONT>    {<a name="line.337"></a>
<FONT color="green">338</FONT>      private final String _text;<a name="line.338"></a>
<FONT color="green">339</FONT>    <a name="line.339"></a>
<FONT color="green">340</FONT>      /**<a name="line.340"></a>
<FONT color="green">341</FONT>       * Constructs a new VigCrack with an encrypted text message to be deciphered.<a name="line.341"></a>
<FONT color="green">342</FONT>       * &lt;p/&gt;<a name="line.342"></a>
<FONT color="green">343</FONT>       * Assumes the message to be deciphered is in English. See <a name="line.343"></a>
<FONT color="green">344</FONT>       * {@link #VigCrack(String, String)} for other languages that can be used.<a name="line.344"></a>
<FONT color="green">345</FONT>       * <a name="line.345"></a>
<FONT color="green">346</FONT>       * @param message The text message to decipher.<a name="line.346"></a>
<FONT color="green">347</FONT>       */<a name="line.347"></a>
<FONT color="green">348</FONT>      public VigCrack(String message)<a name="line.348"></a>
<FONT color="green">349</FONT>      {<a name="line.349"></a>
<FONT color="green">350</FONT>        this(message, "EN");<a name="line.350"></a>
<FONT color="green">351</FONT>      }<a name="line.351"></a>
<FONT color="green">352</FONT>    <a name="line.352"></a>
<FONT color="green">353</FONT>      /**<a name="line.353"></a>
<FONT color="green">354</FONT>       * Constructs a new VigCrack with an encrypted text message, in a user <a name="line.354"></a>
<FONT color="green">355</FONT>       * specified language, to be deciphered.<a name="line.355"></a>
<FONT color="green">356</FONT>       * &lt;p/&gt;<a name="line.356"></a>
<FONT color="green">357</FONT>       * &lt;code&gt;language&lt;/code&gt; is a two character String that indicates which <a name="line.357"></a>
<FONT color="green">358</FONT>       * language to use. Possible values for &lt;code&gt;language&lt;/code&gt; include:<a name="line.358"></a>
<FONT color="green">359</FONT>       * &lt;ul&gt;<a name="line.359"></a>
<FONT color="green">360</FONT>       * &lt;li&gt;EN - for English&lt;/li&gt;<a name="line.360"></a>
<FONT color="green">361</FONT>       * &lt;li&gt;DE - for German&lt;/li&gt;<a name="line.361"></a>
<FONT color="green">362</FONT>       * &lt;li&gt;ES - for Spanish&lt;/li&gt;<a name="line.362"></a>
<FONT color="green">363</FONT>       * &lt;li&gt;FR - for French&lt;/li&gt;<a name="line.363"></a>
<FONT color="green">364</FONT>       * &lt;li&gt;IT - for Italian&lt;/li&gt;<a name="line.364"></a>
<FONT color="green">365</FONT>       * &lt;li&gt;PT - for Portuguese&lt;/li&gt;<a name="line.365"></a>
<FONT color="green">366</FONT>       * &lt;/ul&gt;<a name="line.366"></a>
<FONT color="green">367</FONT>       * <a name="line.367"></a>
<FONT color="green">368</FONT>       * @param message The text message to decipher.<a name="line.368"></a>
<FONT color="green">369</FONT>       * @param language The language of the message.<a name="line.369"></a>
<FONT color="green">370</FONT>       */<a name="line.370"></a>
<FONT color="green">371</FONT>      public VigCrack(String message, String language)<a name="line.371"></a>
<FONT color="green">372</FONT>      {<a name="line.372"></a>
<FONT color="green">373</FONT>        if (message == null)<a name="line.373"></a>
<FONT color="green">374</FONT>        {<a name="line.374"></a>
<FONT color="green">375</FONT>          message = "";<a name="line.375"></a>
<FONT color="green">376</FONT>        }<a name="line.376"></a>
<FONT color="green">377</FONT>        _text = message;<a name="line.377"></a>
<FONT color="green">378</FONT>    <a name="line.378"></a>
<FONT color="green">379</FONT>        if (language == null)<a name="line.379"></a>
<FONT color="green">380</FONT>        {<a name="line.380"></a>
<FONT color="green">381</FONT>          language = "";<a name="line.381"></a>
<FONT color="green">382</FONT>        }<a name="line.382"></a>
<FONT color="green">383</FONT>        language = language.toUpperCase();<a name="line.383"></a>
<FONT color="green">384</FONT>        _lang_data = LanguageData.getData(language);<a name="line.384"></a>
<FONT color="green">385</FONT>        _lang = language;<a name="line.385"></a>
<FONT color="green">386</FONT>      }<a name="line.386"></a>
<FONT color="green">387</FONT>    <a name="line.387"></a>
<FONT color="green">388</FONT>    //  # Unless otherwise specified, test for codewords between (and including)<a name="line.388"></a>
<FONT color="green">389</FONT>    //  # these two lengths:<a name="line.389"></a>
<FONT color="green">390</FONT>    //  __default_min_codeword_length = 5<a name="line.390"></a>
<FONT color="green">391</FONT>    //  __default_max_codeword_length = 9<a name="line.391"></a>
<FONT color="green">392</FONT>    <a name="line.392"></a>
<FONT color="green">393</FONT>      private static final int _default_min_codeword_length = 5;<a name="line.393"></a>
<FONT color="green">394</FONT>      private static final int _default_max_codeword_length = 9;<a name="line.394"></a>
<FONT color="green">395</FONT>    <a name="line.395"></a>
<FONT color="green">396</FONT>    //  # The default language is set to English.<a name="line.396"></a>
<FONT color="green">397</FONT>    //  __lang = 'EN'<a name="line.397"></a>
<FONT color="green">398</FONT>    //  __lang_data = __english_data<a name="line.398"></a>
<FONT color="green">399</FONT>      <a name="line.399"></a>
<FONT color="green">400</FONT>      private final String _lang;<a name="line.400"></a>
<FONT color="green">401</FONT>      private final LanguageData _lang_data;<a name="line.401"></a>
<FONT color="green">402</FONT>    <a name="line.402"></a>
<FONT color="green">403</FONT>    //  # This method sets the lang (__lang) attribute of a VigCrack object.<a name="line.403"></a>
<FONT color="green">404</FONT>    //  def set_language(self, language):<a name="line.404"></a>
<FONT color="green">405</FONT>    //  self.__lang = language.upper()<a name="line.405"></a>
<FONT color="green">406</FONT>    //  if self.__lang == 'DE':<a name="line.406"></a>
<FONT color="green">407</FONT>    //    self.__lang_data = self.__german_data<a name="line.407"></a>
<FONT color="green">408</FONT>    //  elif self.__lang == 'ES':<a name="line.408"></a>
<FONT color="green">409</FONT>    //    self.__lang_data = self.__spanish_data<a name="line.409"></a>
<FONT color="green">410</FONT>    //  elif self.__lang == 'FR':<a name="line.410"></a>
<FONT color="green">411</FONT>    //    self.__lang_data = self.__french_data<a name="line.411"></a>
<FONT color="green">412</FONT>    //  elif self.__lang == 'IT':<a name="line.412"></a>
<FONT color="green">413</FONT>    //    self.__lang_data = self.__italian_data<a name="line.413"></a>
<FONT color="green">414</FONT>    //  elif self.__lang == 'PT':<a name="line.414"></a>
<FONT color="green">415</FONT>    //    self.__lang_data = self.__portuguese_data<a name="line.415"></a>
<FONT color="green">416</FONT>    //  else:<a name="line.416"></a>
<FONT color="green">417</FONT>    //    self.__lang = 'EN'<a name="line.417"></a>
<FONT color="green">418</FONT>    //  return self<a name="line.418"></a>
<FONT color="green">419</FONT>      /*<a name="line.419"></a>
<FONT color="green">420</FONT>       * Only used when new VigCrack instances constructed.  So, moved to <a name="line.420"></a>
<FONT color="green">421</FONT>       * constructor.<a name="line.421"></a>
<FONT color="green">422</FONT>       */<a name="line.422"></a>
<FONT color="green">423</FONT>    //  private VigCrack setLanguage(String language)<a name="line.423"></a>
<FONT color="green">424</FONT>    //  {<a name="line.424"></a>
<FONT color="green">425</FONT>    //    language = language.toUpperCase();<a name="line.425"></a>
<FONT color="green">426</FONT>    //    if (language.equals("DE"))<a name="line.426"></a>
<FONT color="green">427</FONT>    //      _lang_data = new GermanData();<a name="line.427"></a>
<FONT color="green">428</FONT>    //    else if (language.equals("ES"))<a name="line.428"></a>
<FONT color="green">429</FONT>    //      _lang_data = new SpanishData();<a name="line.429"></a>
<FONT color="green">430</FONT>    //    else if (language.equals("FR"))<a name="line.430"></a>
<FONT color="green">431</FONT>    //      _lang_data = new FrenchData();<a name="line.431"></a>
<FONT color="green">432</FONT>    //    else if (language.equals("IT"))<a name="line.432"></a>
<FONT color="green">433</FONT>    //      _lang_data = new ItalianData();<a name="line.433"></a>
<FONT color="green">434</FONT>    //    else if (language.equals("PT"))<a name="line.434"></a>
<FONT color="green">435</FONT>    //      _lang_data = new PortugeseData();<a name="line.435"></a>
<FONT color="green">436</FONT>    //    else<a name="line.436"></a>
<FONT color="green">437</FONT>    //      language = "EN";<a name="line.437"></a>
<FONT color="green">438</FONT>    //<a name="line.438"></a>
<FONT color="green">439</FONT>    //    _lang = language;<a name="line.439"></a>
<FONT color="green">440</FONT>    //    <a name="line.440"></a>
<FONT color="green">441</FONT>    //    return this;<a name="line.441"></a>
<FONT color="green">442</FONT>    //  }<a name="line.442"></a>
<FONT color="green">443</FONT>      <a name="line.443"></a>
<FONT color="green">444</FONT>    //  # Rotate text n places to the right, wrapping around at the end.<a name="line.444"></a>
<FONT color="green">445</FONT>    //  def __rotate_right(self, n):<a name="line.445"></a>
<FONT color="green">446</FONT>    //      cutting_point = len(self) - (n % len(self))<a name="line.446"></a>
<FONT color="green">447</FONT>    //      return self[cutting_point:] + self[:cutting_point]<a name="line.447"></a>
<FONT color="green">448</FONT>      private VigCrack rotateRight(int n)<a name="line.448"></a>
<FONT color="green">449</FONT>      {<a name="line.449"></a>
<FONT color="green">450</FONT>        int cutting_point = _text.length() - (n % _text.length());<a name="line.450"></a>
<FONT color="green">451</FONT>        String text = _text.substring(cutting_point) + _text.substring(0, cutting_point);<a name="line.451"></a>
<FONT color="green">452</FONT>        return new VigCrack(text, _lang);<a name="line.452"></a>
<FONT color="green">453</FONT>      }<a name="line.453"></a>
<FONT color="green">454</FONT>      <a name="line.454"></a>
<FONT color="green">455</FONT>    //  # Get every nth char from a piece of text, from a given starting position.<a name="line.455"></a>
<FONT color="green">456</FONT>    //  def __get_every_nth_char(self, start, n):<a name="line.456"></a>
<FONT color="green">457</FONT>    //      accumulator = []<a name="line.457"></a>
<FONT color="green">458</FONT>    //      for i in range(len(self)):<a name="line.458"></a>
<FONT color="green">459</FONT>    //          if (i % n) == start:<a name="line.459"></a>
<FONT color="green">460</FONT>    //              accumulator.append(self[i])<a name="line.460"></a>
<FONT color="green">461</FONT>    //      return VigCrack(''.join(accumulator)).set_language(self.__lang)<a name="line.461"></a>
<FONT color="green">462</FONT>      private VigCrack getEveryNthChar(int start, int n)<a name="line.462"></a>
<FONT color="green">463</FONT>      {<a name="line.463"></a>
<FONT color="green">464</FONT>        StringBuilder accumulator = new StringBuilder();<a name="line.464"></a>
<FONT color="green">465</FONT>        for (int i = 0; i &lt; _text.length(); i++)<a name="line.465"></a>
<FONT color="green">466</FONT>        {<a name="line.466"></a>
<FONT color="green">467</FONT>          if ((i % n) == start)<a name="line.467"></a>
<FONT color="green">468</FONT>          {<a name="line.468"></a>
<FONT color="green">469</FONT>            accumulator.append(_text.charAt(i));<a name="line.469"></a>
<FONT color="green">470</FONT>          }<a name="line.470"></a>
<FONT color="green">471</FONT>        }<a name="line.471"></a>
<FONT color="green">472</FONT>        return new VigCrack(accumulator.toString(), _lang);<a name="line.472"></a>
<FONT color="green">473</FONT>      }<a name="line.473"></a>
<FONT color="green">474</FONT>      <a name="line.474"></a>
<FONT color="green">475</FONT>    //  # Build a dictionary containing the number of occurrences of each char.<a name="line.475"></a>
<FONT color="green">476</FONT>    //  def __count_char_freqs(self):<a name="line.476"></a>
<FONT color="green">477</FONT>    //      dictionary = {}<a name="line.477"></a>
<FONT color="green">478</FONT>    //      self = self.upper()<a name="line.478"></a>
<FONT color="green">479</FONT>    //      for char in self:<a name="line.479"></a>
<FONT color="green">480</FONT>    //          if char.isalpha():<a name="line.480"></a>
<FONT color="green">481</FONT>    //              dictionary[char] = dictionary.get(char, 0) + 1<a name="line.481"></a>
<FONT color="green">482</FONT>    //      return dictionary<a name="line.482"></a>
<FONT color="green">483</FONT>      private Map&lt;Character, Double&gt; countCharFreqs()<a name="line.483"></a>
<FONT color="green">484</FONT>      {<a name="line.484"></a>
<FONT color="green">485</FONT>        Map&lt;Character, Double&gt; dictionary = new HashMap&lt;Character, Double&gt;();<a name="line.485"></a>
<FONT color="green">486</FONT>        String text = _text.toUpperCase(); // Didn't change this VigCrack, because not necessary, and may be an unexpected side effect.<a name="line.486"></a>
<FONT color="green">487</FONT>        for (char c : text.toCharArray())<a name="line.487"></a>
<FONT color="green">488</FONT>        {<a name="line.488"></a>
<FONT color="green">489</FONT>          if (isAlpha(c))<a name="line.489"></a>
<FONT color="green">490</FONT>          {<a name="line.490"></a>
<FONT color="green">491</FONT>            Double i = dictionary.get(c);<a name="line.491"></a>
<FONT color="green">492</FONT>            i = (i == null) ? 0 : i;<a name="line.492"></a>
<FONT color="green">493</FONT>            dictionary.put(c, i + 1);<a name="line.493"></a>
<FONT color="green">494</FONT>          }<a name="line.494"></a>
<FONT color="green">495</FONT>        }<a name="line.495"></a>
<FONT color="green">496</FONT>        return dictionary;<a name="line.496"></a>
<FONT color="green">497</FONT>      }<a name="line.497"></a>
<FONT color="green">498</FONT>      <a name="line.498"></a>
<FONT color="green">499</FONT>    //  # Scale the dictionary so that it can be compared with __lang_data.<a name="line.499"></a>
<FONT color="green">500</FONT>    //  def __scale(self, dictionary):<a name="line.500"></a>
<FONT color="green">501</FONT>    //      v = dictionary.values()<a name="line.501"></a>
<FONT color="green">502</FONT>    //      v.sort()<a name="line.502"></a>
<FONT color="green">503</FONT>    //      max_val = v[-1]<a name="line.503"></a>
<FONT color="green">504</FONT>    //      scaling_factor = self.__lang_data['max_val']/max_val<a name="line.504"></a>
<FONT color="green">505</FONT>    //      for (k, v) in dictionary.items():<a name="line.505"></a>
<FONT color="green">506</FONT>    //          dictionary[k] = v*scaling_factor<a name="line.506"></a>
<FONT color="green">507</FONT>    //      return dictionary<a name="line.507"></a>
<FONT color="green">508</FONT>      private Map&lt;Character, Double&gt; scale(Map&lt;Character, Double&gt; dictionary)<a name="line.508"></a>
<FONT color="green">509</FONT>      {<a name="line.509"></a>
<FONT color="green">510</FONT>        List&lt;Double&gt; v = new ArrayList&lt;Double&gt;(dictionary.values());<a name="line.510"></a>
<FONT color="green">511</FONT>        Collections.sort(v);<a name="line.511"></a>
<FONT color="green">512</FONT>        double max_val = v.get(v.size() - 1);<a name="line.512"></a>
<FONT color="green">513</FONT>        double scaling_factor = _lang_data._max_value / max_val;<a name="line.513"></a>
<FONT color="green">514</FONT>        for (Character k : dictionary.keySet())<a name="line.514"></a>
<FONT color="green">515</FONT>        {<a name="line.515"></a>
<FONT color="green">516</FONT>          dictionary.put(k, dictionary.get(k) * scaling_factor);<a name="line.516"></a>
<FONT color="green">517</FONT>        }<a name="line.517"></a>
<FONT color="green">518</FONT>        return dictionary;<a name="line.518"></a>
<FONT color="green">519</FONT>      }<a name="line.519"></a>
<FONT color="green">520</FONT>      <a name="line.520"></a>
<FONT color="green">521</FONT>    //  # The residual error is the difference between a char's frequency in<a name="line.521"></a>
<FONT color="green">522</FONT>    //  # __lang_data and its frequency in the scaled dictionary from above.<a name="line.522"></a>
<FONT color="green">523</FONT>    //  # The error is then squared to remove a possible negative value.<a name="line.523"></a>
<FONT color="green">524</FONT>    //  def __sum_residuals_squared(self, dictionary):<a name="line.524"></a>
<FONT color="green">525</FONT>    //      sum = 0<a name="line.525"></a>
<FONT color="green">526</FONT>    //      for (k, v) in dictionary.items():<a name="line.526"></a>
<FONT color="green">527</FONT>    //          sum += (v - self.__lang_data[k])**2<a name="line.527"></a>
<FONT color="green">528</FONT>    //      return sum<a name="line.528"></a>
<FONT color="green">529</FONT>      private double sumResidualsSquared(Map&lt;Character, Double&gt; dictionary)<a name="line.529"></a>
<FONT color="green">530</FONT>      {<a name="line.530"></a>
<FONT color="green">531</FONT>        double sum = 0;<a name="line.531"></a>
<FONT color="green">532</FONT>        for (Character k : dictionary.keySet())<a name="line.532"></a>
<FONT color="green">533</FONT>        {<a name="line.533"></a>
<FONT color="green">534</FONT>          Double v = dictionary.get(k);<a name="line.534"></a>
<FONT color="green">535</FONT>          sum += (v - _lang_data._frequencies.get(k)) * (v - _lang_data._frequencies.get(k));<a name="line.535"></a>
<FONT color="green">536</FONT>        }<a name="line.536"></a>
<FONT color="green">537</FONT>        return sum;<a name="line.537"></a>
<FONT color="green">538</FONT>      }<a name="line.538"></a>
<FONT color="green">539</FONT>      <a name="line.539"></a>
<FONT color="green">540</FONT>    //  # Find the Caesar shift that brings the ciphertext closest to the<a name="line.540"></a>
<FONT color="green">541</FONT>    //  # character distribution of the plaintext's language.<a name="line.541"></a>
<FONT color="green">542</FONT>    //  def __find_best_caesar_shift(self):<a name="line.542"></a>
<FONT color="green">543</FONT>    //      best = 0<a name="line.543"></a>
<FONT color="green">544</FONT>    //      smallest_sum = -1<a name="line.544"></a>
<FONT color="green">545</FONT>    //      # Find the residual sum for each shift.<a name="line.545"></a>
<FONT color="green">546</FONT>    //      for shift in range(26):<a name="line.546"></a>
<FONT color="green">547</FONT>    //          encoded_text = Caesar(self).encipher(shift)<a name="line.547"></a>
<FONT color="green">548</FONT>    //          vigcrack_obj = VigCrack(encoded_text).set_language(self.__lang)<a name="line.548"></a>
<FONT color="green">549</FONT>    //          char_freqs = vigcrack_obj.__count_char_freqs()<a name="line.549"></a>
<FONT color="green">550</FONT>    //          scaled = vigcrack_obj.__scale(char_freqs)<a name="line.550"></a>
<FONT color="green">551</FONT>    //          current_sum = vigcrack_obj.__sum_residuals_squared(scaled)<a name="line.551"></a>
<FONT color="green">552</FONT>    //          # Keep track of the shift with the lowest residual sum.<a name="line.552"></a>
<FONT color="green">553</FONT>    //          # If there's a tie, the smallest shift wins.<a name="line.553"></a>
<FONT color="green">554</FONT>    //          if smallest_sum == -1:<a name="line.554"></a>
<FONT color="green">555</FONT>    //              smallest_sum = current_sum<a name="line.555"></a>
<FONT color="green">556</FONT>    //          if current_sum &lt; smallest_sum:<a name="line.556"></a>
<FONT color="green">557</FONT>    //              best = shift<a name="line.557"></a>
<FONT color="green">558</FONT>    //              smallest_sum = current_sum<a name="line.558"></a>
<FONT color="green">559</FONT>    //      return best<a name="line.559"></a>
<FONT color="green">560</FONT>      private int findBestCaesarShift()<a name="line.560"></a>
<FONT color="green">561</FONT>      {<a name="line.561"></a>
<FONT color="green">562</FONT>        int best = 0;<a name="line.562"></a>
<FONT color="green">563</FONT>        double smallest_sum = -1D;<a name="line.563"></a>
<FONT color="green">564</FONT>        for (int shift = 0; shift &lt; 26; shift++)<a name="line.564"></a>
<FONT color="green">565</FONT>        {<a name="line.565"></a>
<FONT color="green">566</FONT>          String encoded_text = new Caesar(_text).encipher(shift).text();<a name="line.566"></a>
<FONT color="green">567</FONT>          VigCrack vigcrack_obj = new VigCrack(encoded_text, _lang);<a name="line.567"></a>
<FONT color="green">568</FONT>          Map&lt;Character, Double&gt; char_freqs = vigcrack_obj.countCharFreqs();<a name="line.568"></a>
<FONT color="green">569</FONT>          Map&lt;Character, Double&gt; scaled = vigcrack_obj.scale(char_freqs);<a name="line.569"></a>
<FONT color="green">570</FONT>          double current_sum = vigcrack_obj.sumResidualsSquared(scaled);<a name="line.570"></a>
<FONT color="green">571</FONT>    <a name="line.571"></a>
<FONT color="green">572</FONT>          if (smallest_sum == -1)<a name="line.572"></a>
<FONT color="green">573</FONT>          {<a name="line.573"></a>
<FONT color="green">574</FONT>            smallest_sum = current_sum;<a name="line.574"></a>
<FONT color="green">575</FONT>          }<a name="line.575"></a>
<FONT color="green">576</FONT>          if (current_sum &lt; smallest_sum)<a name="line.576"></a>
<FONT color="green">577</FONT>          {<a name="line.577"></a>
<FONT color="green">578</FONT>            best = shift;<a name="line.578"></a>
<FONT color="green">579</FONT>            smallest_sum = current_sum;<a name="line.579"></a>
<FONT color="green">580</FONT>          }<a name="line.580"></a>
<FONT color="green">581</FONT>        }<a name="line.581"></a>
<FONT color="green">582</FONT>        return best;<a name="line.582"></a>
<FONT color="green">583</FONT>      }<a name="line.583"></a>
<FONT color="green">584</FONT>      <a name="line.584"></a>
<FONT color="green">585</FONT>    //  def __find_codeword_length(self, min_length, max_length):<a name="line.585"></a>
<FONT color="green">586</FONT>    //      codeword_length = min_length<a name="line.586"></a>
<FONT color="green">587</FONT>    //      kappas = []<a name="line.587"></a>
<FONT color="green">588</FONT>    //      # Put the kappa value for each codeword length tested into an array.<a name="line.588"></a>
<FONT color="green">589</FONT>    //      for i in range(min_length, max_length + 1):<a name="line.589"></a>
<FONT color="green">590</FONT>    //          temp = self.__rotate_right(i)<a name="line.590"></a>
<FONT color="green">591</FONT>    //          coincidences = 0<a name="line.591"></a>
<FONT color="green">592</FONT>    //          for j in range(len(self)):<a name="line.592"></a>
<FONT color="green">593</FONT>    //              if temp[j] == self[j]:<a name="line.593"></a>
<FONT color="green">594</FONT>    //                  coincidences += 1<a name="line.594"></a>
<FONT color="green">595</FONT>    //          kappas.append(float(coincidences)/len(self))<a name="line.595"></a>
<FONT color="green">596</FONT>    //      # Find out which value of kappa is closest to the kappa of the<a name="line.596"></a>
<FONT color="green">597</FONT>    //      # plaintext's language.  If there's a tie, the shortest codeword wins.<a name="line.597"></a>
<FONT color="green">598</FONT>    //      smallest_squared_diff = -1<a name="line.598"></a>
<FONT color="green">599</FONT>    //      for i in range((max_length + 1) - min_length):<a name="line.599"></a>
<FONT color="green">600</FONT>    //          current_squared_diff = (self.__lang_data['kappa'] - kappas[i])**2<a name="line.600"></a>
<FONT color="green">601</FONT>    //          if smallest_squared_diff == -1:<a name="line.601"></a>
<FONT color="green">602</FONT>    //              smallest_squared_diff = current_squared_diff<a name="line.602"></a>
<FONT color="green">603</FONT>    //          if current_squared_diff &lt; smallest_squared_diff:<a name="line.603"></a>
<FONT color="green">604</FONT>    //              codeword_length = min_length + i<a name="line.604"></a>
<FONT color="green">605</FONT>    //              smallest_squared_diff = current_squared_diff<a name="line.605"></a>
<FONT color="green">606</FONT>    //      return codeword_length<a name="line.606"></a>
<FONT color="green">607</FONT>      private int findCodewordLength(int min_length, int max_length)<a name="line.607"></a>
<FONT color="green">608</FONT>      {<a name="line.608"></a>
<FONT color="green">609</FONT>        int codeword_length = min_length;<a name="line.609"></a>
<FONT color="green">610</FONT>        List&lt;Double&gt; kappas = new ArrayList&lt;Double&gt;();<a name="line.610"></a>
<FONT color="green">611</FONT>    <a name="line.611"></a>
<FONT color="green">612</FONT>        for (int i = min_length; i &lt; max_length + 1; i++)<a name="line.612"></a>
<FONT color="green">613</FONT>        {<a name="line.613"></a>
<FONT color="green">614</FONT>          VigCrack temp = rotateRight(i);<a name="line.614"></a>
<FONT color="green">615</FONT>          int coincidences = 0;<a name="line.615"></a>
<FONT color="green">616</FONT>          for (int j = 0; j &lt; _text.length(); j++)<a name="line.616"></a>
<FONT color="green">617</FONT>          {<a name="line.617"></a>
<FONT color="green">618</FONT>            if (temp._text.charAt(j) == _text.charAt(j))<a name="line.618"></a>
<FONT color="green">619</FONT>            {<a name="line.619"></a>
<FONT color="green">620</FONT>              coincidences += 1;<a name="line.620"></a>
<FONT color="green">621</FONT>            }<a name="line.621"></a>
<FONT color="green">622</FONT>          }<a name="line.622"></a>
<FONT color="green">623</FONT>          kappas.add(((double)coincidences) / _text.length());<a name="line.623"></a>
<FONT color="green">624</FONT>        }<a name="line.624"></a>
<FONT color="green">625</FONT>    <a name="line.625"></a>
<FONT color="green">626</FONT>        double smallest_squared_diff = -1D;<a name="line.626"></a>
<FONT color="green">627</FONT>        for (int i = 0; i &lt; max_length + 1 - min_length; i++)<a name="line.627"></a>
<FONT color="green">628</FONT>        {<a name="line.628"></a>
<FONT color="green">629</FONT>          double current_squared_diff = (_lang_data._kappa - kappas.get(i)) * (_lang_data._kappa - kappas.get(i));<a name="line.629"></a>
<FONT color="green">630</FONT>          if (smallest_squared_diff == -1)<a name="line.630"></a>
<FONT color="green">631</FONT>          {<a name="line.631"></a>
<FONT color="green">632</FONT>            smallest_squared_diff = current_squared_diff;<a name="line.632"></a>
<FONT color="green">633</FONT>          }<a name="line.633"></a>
<FONT color="green">634</FONT>          if (current_squared_diff &lt; smallest_squared_diff)<a name="line.634"></a>
<FONT color="green">635</FONT>          {<a name="line.635"></a>
<FONT color="green">636</FONT>            codeword_length = min_length + i;<a name="line.636"></a>
<FONT color="green">637</FONT>            smallest_squared_diff = current_squared_diff;<a name="line.637"></a>
<FONT color="green">638</FONT>          }<a name="line.638"></a>
<FONT color="green">639</FONT>        }<a name="line.639"></a>
<FONT color="green">640</FONT>        <a name="line.640"></a>
<FONT color="green">641</FONT>        return codeword_length;<a name="line.641"></a>
<FONT color="green">642</FONT>      }<a name="line.642"></a>
<FONT color="green">643</FONT>      <a name="line.643"></a>
<FONT color="green">644</FONT>    //  def __find_codeword(self, min_length, max_length):<a name="line.644"></a>
<FONT color="green">645</FONT>    //      # Strip away invalid chars.<a name="line.645"></a>
<FONT color="green">646</FONT>    //      accumulator = []<a name="line.646"></a>
<FONT color="green">647</FONT>    //      for char in self:<a name="line.647"></a>
<FONT color="green">648</FONT>    //          if char.isalpha():<a name="line.648"></a>
<FONT color="green">649</FONT>    //              accumulator.append(char)<a name="line.649"></a>
<FONT color="green">650</FONT>    //      alpha_only = VigCrack(''.join(accumulator)).set_language(self.__lang)<a name="line.650"></a>
<FONT color="green">651</FONT>    //      codeword_length = alpha_only.__find_codeword_length(min_length,<a name="line.651"></a>
<FONT color="green">652</FONT>    //                                                          max_length)<a name="line.652"></a>
<FONT color="green">653</FONT>    //      # Build the codeword by finding one character at a time.<a name="line.653"></a>
<FONT color="green">654</FONT>    //      codeword = []<a name="line.654"></a>
<FONT color="green">655</FONT>    //      for i in range(codeword_length):<a name="line.655"></a>
<FONT color="green">656</FONT>    //          temp = alpha_only.__get_every_nth_char(i, codeword_length)<a name="line.656"></a>
<FONT color="green">657</FONT>    //          shift = temp.__find_best_caesar_shift()<a name="line.657"></a>
<FONT color="green">658</FONT>    //          if shift == 0:<a name="line.658"></a>
<FONT color="green">659</FONT>    //              codeword.append('A')<a name="line.659"></a>
<FONT color="green">660</FONT>    //          else:<a name="line.660"></a>
<FONT color="green">661</FONT>    //              codeword.append(chr(ord('A') + (26 - shift)))<a name="line.661"></a>
<FONT color="green">662</FONT>    //      return VigCrack(''.join(codeword)).set_language(self.__lang)<a name="line.662"></a>
<FONT color="green">663</FONT>      private String findCodeword(int min_length, int max_length)<a name="line.663"></a>
<FONT color="green">664</FONT>      {<a name="line.664"></a>
<FONT color="green">665</FONT>        StringBuilder accumulator = new StringBuilder();<a name="line.665"></a>
<FONT color="green">666</FONT>        for (char c : _text.toCharArray())<a name="line.666"></a>
<FONT color="green">667</FONT>        {<a name="line.667"></a>
<FONT color="green">668</FONT>          if (isAlpha(c))<a name="line.668"></a>
<FONT color="green">669</FONT>          {<a name="line.669"></a>
<FONT color="green">670</FONT>            accumulator.append(c);<a name="line.670"></a>
<FONT color="green">671</FONT>          }<a name="line.671"></a>
<FONT color="green">672</FONT>        }<a name="line.672"></a>
<FONT color="green">673</FONT>        VigCrack alpha_only = new VigCrack(accumulator.toString(), _lang);<a name="line.673"></a>
<FONT color="green">674</FONT>        int codeword_length = alpha_only.findCodewordLength(min_length, max_length);<a name="line.674"></a>
<FONT color="green">675</FONT>    <a name="line.675"></a>
<FONT color="green">676</FONT>        StringBuilder codeword = new StringBuilder();<a name="line.676"></a>
<FONT color="green">677</FONT>        for (int i = 0; i &lt; codeword_length; i++)<a name="line.677"></a>
<FONT color="green">678</FONT>        {<a name="line.678"></a>
<FONT color="green">679</FONT>          VigCrack temp = alpha_only.getEveryNthChar(i, codeword_length);<a name="line.679"></a>
<FONT color="green">680</FONT>          int shift = temp.findBestCaesarShift();<a name="line.680"></a>
<FONT color="green">681</FONT>          if (shift == 0)<a name="line.681"></a>
<FONT color="green">682</FONT>          {<a name="line.682"></a>
<FONT color="green">683</FONT>            codeword.append('A');<a name="line.683"></a>
<FONT color="green">684</FONT>          }<a name="line.684"></a>
<FONT color="green">685</FONT>          else<a name="line.685"></a>
<FONT color="green">686</FONT>          {<a name="line.686"></a>
<FONT color="green">687</FONT>            codeword.append((char)(((int)'A') + (26 - shift)));<a name="line.687"></a>
<FONT color="green">688</FONT>          }<a name="line.688"></a>
<FONT color="green">689</FONT>        }<a name="line.689"></a>
<FONT color="green">690</FONT>        return codeword.toString();<a name="line.690"></a>
<FONT color="green">691</FONT>      }<a name="line.691"></a>
<FONT color="green">692</FONT>      <a name="line.692"></a>
<FONT color="green">693</FONT>    //  def __parse_args(self, *arg_list):<a name="line.693"></a>
<FONT color="green">694</FONT>    //      if len(arg_list) == 0:    # Use default values for codeword length.<a name="line.694"></a>
<FONT color="green">695</FONT>    //          min_length = self.__default_min_codeword_length<a name="line.695"></a>
<FONT color="green">696</FONT>    //          max_length = self.__default_max_codeword_length<a name="line.696"></a>
<FONT color="green">697</FONT>    //      elif len(arg_list) == 1:    # Exact codeword length specified by user.<a name="line.697"></a>
<FONT color="green">698</FONT>    //          min_length = max_length = int(arg_list[0])<a name="line.698"></a>
<FONT color="green">699</FONT>    //      else:    # min_length and max_length given by user.<a name="line.699"></a>
<FONT color="green">700</FONT>    //          min_length = int(arg_list[0])<a name="line.700"></a>
<FONT color="green">701</FONT>    //          max_length = int(arg_list[1])<a name="line.701"></a>
<FONT color="green">702</FONT>    //      # Check for input errors.<a name="line.702"></a>
<FONT color="green">703</FONT>    //      if min_length == max_length:<a name="line.703"></a>
<FONT color="green">704</FONT>    //          if min_length &lt; 1:<a name="line.704"></a>
<FONT color="green">705</FONT>    //              raise InputError('Codeword length is too small')<a name="line.705"></a>
<FONT color="green">706</FONT>    //      else:<a name="line.706"></a>
<FONT color="green">707</FONT>    //          if min_length &lt; 1:<a name="line.707"></a>
<FONT color="green">708</FONT>    //              raise InputError('min_length is too small')<a name="line.708"></a>
<FONT color="green">709</FONT>    //          if max_length &lt; 1:<a name="line.709"></a>
<FONT color="green">710</FONT>    //              raise InputError('max_length is too small')<a name="line.710"></a>
<FONT color="green">711</FONT>    //      if max_length &lt; min_length:<a name="line.711"></a>
<FONT color="green">712</FONT>    //          raise InputError('max_length cannot be shorter than min_length')<a name="line.712"></a>
<FONT color="green">713</FONT>    //      if len(self) == 0:<a name="line.713"></a>
<FONT color="green">714</FONT>    //          raise InputError('Ciphertext is empty')<a name="line.714"></a>
<FONT color="green">715</FONT>    //      if len(self) &lt; max_length:<a name="line.715"></a>
<FONT color="green">716</FONT>    //          raise InputError('Ciphertext is too short')<a name="line.716"></a>
<FONT color="green">717</FONT>    //      # Check that the ciphertext contains at least one valid character.<a name="line.717"></a>
<FONT color="green">718</FONT>    //      has_valid_char = False<a name="line.718"></a>
<FONT color="green">719</FONT>    //      for char in self:<a name="line.719"></a>
<FONT color="green">720</FONT>    //          if char.isalpha():<a name="line.720"></a>
<FONT color="green">721</FONT>    //              has_valid_char = True<a name="line.721"></a>
<FONT color="green">722</FONT>    //              break<a name="line.722"></a>
<FONT color="green">723</FONT>    //      if not has_valid_char:<a name="line.723"></a>
<FONT color="green">724</FONT>    //          raise InputError('No valid characters in ciphertext')<a name="line.724"></a>
<FONT color="green">725</FONT>    //      # If everything's all right, return the min_length and max_length.<a name="line.725"></a>
<FONT color="green">726</FONT>    //      return [min_length, max_length]<a name="line.726"></a>
<FONT color="green">727</FONT>      private int[] parseArgs(String[] arg_list)<a name="line.727"></a>
<FONT color="green">728</FONT>      {<a name="line.728"></a>
<FONT color="green">729</FONT>        int min_length = _default_min_codeword_length;<a name="line.729"></a>
<FONT color="green">730</FONT>        int max_length = _default_max_codeword_length;<a name="line.730"></a>
<FONT color="green">731</FONT>        if (arg_list != null)<a name="line.731"></a>
<FONT color="green">732</FONT>        {<a name="line.732"></a>
<FONT color="green">733</FONT>          if (arg_list.length == 1)<a name="line.733"></a>
<FONT color="green">734</FONT>          {<a name="line.734"></a>
<FONT color="green">735</FONT>            min_length = Integer.parseInt(arg_list[0]);<a name="line.735"></a>
<FONT color="green">736</FONT>            max_length = min_length;<a name="line.736"></a>
<FONT color="green">737</FONT>          }<a name="line.737"></a>
<FONT color="green">738</FONT>          else if (arg_list.length &gt; 1)<a name="line.738"></a>
<FONT color="green">739</FONT>          {<a name="line.739"></a>
<FONT color="green">740</FONT>            min_length = Integer.parseInt(arg_list[0]);<a name="line.740"></a>
<FONT color="green">741</FONT>            max_length = Integer.parseInt(arg_list[1]);<a name="line.741"></a>
<FONT color="green">742</FONT>          }<a name="line.742"></a>
<FONT color="green">743</FONT>        }<a name="line.743"></a>
<FONT color="green">744</FONT>    <a name="line.744"></a>
<FONT color="green">745</FONT>        if (min_length == max_length)<a name="line.745"></a>
<FONT color="green">746</FONT>        {<a name="line.746"></a>
<FONT color="green">747</FONT>          if (min_length &lt; 1)<a name="line.747"></a>
<FONT color="green">748</FONT>          {<a name="line.748"></a>
<FONT color="green">749</FONT>            throw new InputError("Codeword length is too small");<a name="line.749"></a>
<FONT color="green">750</FONT>          }<a name="line.750"></a>
<FONT color="green">751</FONT>        }<a name="line.751"></a>
<FONT color="green">752</FONT>        else<a name="line.752"></a>
<FONT color="green">753</FONT>        {<a name="line.753"></a>
<FONT color="green">754</FONT>          if (min_length &lt; 1)<a name="line.754"></a>
<FONT color="green">755</FONT>          {<a name="line.755"></a>
<FONT color="green">756</FONT>            throw new InputError("min_length is too small");<a name="line.756"></a>
<FONT color="green">757</FONT>          }<a name="line.757"></a>
<FONT color="green">758</FONT>          if (max_length &lt; 1)<a name="line.758"></a>
<FONT color="green">759</FONT>          {<a name="line.759"></a>
<FONT color="green">760</FONT>            throw new InputError("max_length is too small");<a name="line.760"></a>
<FONT color="green">761</FONT>          }<a name="line.761"></a>
<FONT color="green">762</FONT>        }<a name="line.762"></a>
<FONT color="green">763</FONT>        if (max_length &lt; min_length)<a name="line.763"></a>
<FONT color="green">764</FONT>        {<a name="line.764"></a>
<FONT color="green">765</FONT>          throw new InputError("max_length cannot be shorter than min_length");<a name="line.765"></a>
<FONT color="green">766</FONT>        }<a name="line.766"></a>
<FONT color="green">767</FONT>        if (_text.length() == 0)<a name="line.767"></a>
<FONT color="green">768</FONT>        {<a name="line.768"></a>
<FONT color="green">769</FONT>          throw new InputError("Ciphertext is empty");<a name="line.769"></a>
<FONT color="green">770</FONT>        }<a name="line.770"></a>
<FONT color="green">771</FONT>        if (_text.length() &lt; max_length)<a name="line.771"></a>
<FONT color="green">772</FONT>        {<a name="line.772"></a>
<FONT color="green">773</FONT>          throw new InputError("Ciphertext is too short");<a name="line.773"></a>
<FONT color="green">774</FONT>        }<a name="line.774"></a>
<FONT color="green">775</FONT>    <a name="line.775"></a>
<FONT color="green">776</FONT>        boolean has_valid_char = false;<a name="line.776"></a>
<FONT color="green">777</FONT>        for (char c : _text.toCharArray())<a name="line.777"></a>
<FONT color="green">778</FONT>        {<a name="line.778"></a>
<FONT color="green">779</FONT>          if (isAlpha(c))<a name="line.779"></a>
<FONT color="green">780</FONT>          {<a name="line.780"></a>
<FONT color="green">781</FONT>            has_valid_char = true;<a name="line.781"></a>
<FONT color="green">782</FONT>            break;<a name="line.782"></a>
<FONT color="green">783</FONT>          }<a name="line.783"></a>
<FONT color="green">784</FONT>        }<a name="line.784"></a>
<FONT color="green">785</FONT>        if (!has_valid_char)<a name="line.785"></a>
<FONT color="green">786</FONT>        {<a name="line.786"></a>
<FONT color="green">787</FONT>          throw new InputError("No valid characters in ciphertext");<a name="line.787"></a>
<FONT color="green">788</FONT>        }<a name="line.788"></a>
<FONT color="green">789</FONT>        return new int[] {min_length, max_length};<a name="line.789"></a>
<FONT color="green">790</FONT>      }<a name="line.790"></a>
<FONT color="green">791</FONT>    <a name="line.791"></a>
<FONT color="green">792</FONT>      /**<a name="line.792"></a>
<FONT color="green">793</FONT>       * Attempts to discover the key used to encrypt the internal message.<a name="line.793"></a>
<FONT color="green">794</FONT>       * &lt;p/&gt;<a name="line.794"></a>
<FONT color="green">795</FONT>       * If the provided arg_list is null or empty, then keys with lengths in the <a name="line.795"></a>
<FONT color="green">796</FONT>       * range of 5 to 9 (inclusive) are used. Otherwise, arg_list should have  <a name="line.796"></a>
<FONT color="green">797</FONT>       * either one or two components, and the components should be String <a name="line.797"></a>
<FONT color="green">798</FONT>       * representations of integral numbers, e.g., "5", "6". If only one component <a name="line.798"></a>
<FONT color="green">799</FONT>       * is provided, only keys of that length are sought.  If two components are <a name="line.799"></a>
<FONT color="green">800</FONT>       * provided, then keys with lengths in the range represented by the two <a name="line.800"></a>
<FONT color="green">801</FONT>       * components are sought.  For example, if arg_list is {"3", "5"}, then keys <a name="line.801"></a>
<FONT color="green">802</FONT>       * with lengths 3, 4, and 5 are sought. The one key that best decrypts the <a name="line.802"></a>
<FONT color="green">803</FONT>       * internal encrypted message is used.<a name="line.803"></a>
<FONT color="green">804</FONT>       * <a name="line.804"></a>
<FONT color="green">805</FONT>       * @param     arg_list Optional length range within which to look for the key  <a name="line.805"></a>
<FONT color="green">806</FONT>       *            used to encrypt the internal message.<a name="line.806"></a>
<FONT color="green">807</FONT>       * @return    The key used to encrypt the internal encrypted message.<a name="line.807"></a>
<FONT color="green">808</FONT>       */<a name="line.808"></a>
<FONT color="green">809</FONT>    //  def crack_codeword(self, *arg_list):<a name="line.809"></a>
<FONT color="green">810</FONT>    //      """<a name="line.810"></a>
<FONT color="green">811</FONT>    //      Try to find the codeword that encrypted the ciphertext object.<a name="line.811"></a>
<FONT color="green">812</FONT>    //      If no arguments are supplied, codewords between the default minimum<a name="line.812"></a>
<FONT color="green">813</FONT>    //      length and the default maximum length are tried.<a name="line.813"></a>
<FONT color="green">814</FONT>    //      If one integer argument is supplied, only codewords with that length<a name="line.814"></a>
<FONT color="green">815</FONT>    //      will be tried.<a name="line.815"></a>
<FONT color="green">816</FONT>    //      If two integer arguments are given then the first argument is treated<a name="line.816"></a>
<FONT color="green">817</FONT>    //      as a minimum codeword length, and the second argument is treated as a<a name="line.817"></a>
<FONT color="green">818</FONT>    //      maximum codeword length, to try.<a name="line.818"></a>
<FONT color="green">819</FONT>    //      """<a name="line.819"></a>
<FONT color="green">820</FONT>    //      array = self.__parse_args(*arg_list)<a name="line.820"></a>
<FONT color="green">821</FONT>    //      return self.__find_codeword(array[0], array[1])<a name="line.821"></a>
<FONT color="green">822</FONT>      public String crackCodeword(String[] arg_list)<a name="line.822"></a>
<FONT color="green">823</FONT>      {<a name="line.823"></a>
<FONT color="green">824</FONT>        int[] array = parseArgs(arg_list);<a name="line.824"></a>
<FONT color="green">825</FONT>        return findCodeword(array[0], array[1]);<a name="line.825"></a>
<FONT color="green">826</FONT>      }<a name="line.826"></a>
<FONT color="green">827</FONT>    <a name="line.827"></a>
<FONT color="green">828</FONT>      /**<a name="line.828"></a>
<FONT color="green">829</FONT>       * Attempts to discover the plain text message of the internal encrypted <a name="line.829"></a>
<FONT color="green">830</FONT>       * message.<a name="line.830"></a>
<FONT color="green">831</FONT>       * &lt;p/&gt;<a name="line.831"></a>
<FONT color="green">832</FONT>       * If the provided arg_list is null or empty, then keys with lengths in the <a name="line.832"></a>
<FONT color="green">833</FONT>       * range of 5 to 9 (inclusive) are used. Otherwise, arg_list should have  <a name="line.833"></a>
<FONT color="green">834</FONT>       * either one or two components, and the components should be String <a name="line.834"></a>
<FONT color="green">835</FONT>       * representations of integral numbers, e.g., "5", "6". If only one component <a name="line.835"></a>
<FONT color="green">836</FONT>       * is provided, only keys of that length are sought.  If two components are <a name="line.836"></a>
<FONT color="green">837</FONT>       * provided, then keys with lengths in the range represented by the two <a name="line.837"></a>
<FONT color="green">838</FONT>       * components are sought.  For example, if arg_list is {"3", "5"}, then keys <a name="line.838"></a>
<FONT color="green">839</FONT>       * with lengths 3, 4, and 5 are sought. The one key that best decrypts the <a name="line.839"></a>
<FONT color="green">840</FONT>       * internal encrypted message is used. <a name="line.840"></a>
<FONT color="green">841</FONT>       * <a name="line.841"></a>
<FONT color="green">842</FONT>       * @param     arg_list Optional length range within which to look for the key  <a name="line.842"></a>
<FONT color="green">843</FONT>       *            used to encrypt the internal message.<a name="line.843"></a>
<FONT color="green">844</FONT>       * @return    The plain text message, decrypted from the internal encrypted <a name="line.844"></a>
<FONT color="green">845</FONT>       *            message.<a name="line.845"></a>
<FONT color="green">846</FONT>       */<a name="line.846"></a>
<FONT color="green">847</FONT>    //  def crack_message(self, *arg_list):<a name="line.847"></a>
<FONT color="green">848</FONT>    //      """<a name="line.848"></a>
<FONT color="green">849</FONT>    //      Try to decode the ciphertext object.<a name="line.849"></a>
<FONT color="green">850</FONT>    //      This method accepts arguments in the same way as the crack_codeword()<a name="line.850"></a>
<FONT color="green">851</FONT>    //      method.<a name="line.851"></a>
<FONT color="green">852</FONT>    //      """<a name="line.852"></a>
<FONT color="green">853</FONT>    //      codeword = self.crack_codeword(*arg_list)<a name="line.853"></a>
<FONT color="green">854</FONT>    //      return self.decipher(codeword)<a name="line.854"></a>
<FONT color="green">855</FONT>      public String crackMessage(String[] arg_list)<a name="line.855"></a>
<FONT color="green">856</FONT>      {<a name="line.856"></a>
<FONT color="green">857</FONT>        String codeword = crackCodeword(arg_list);<a name="line.857"></a>
<FONT color="green">858</FONT>        return new Vigenere(_text).decipher(codeword).text();<a name="line.858"></a>
<FONT color="green">859</FONT>      }<a name="line.859"></a>
<FONT color="green">860</FONT>    <a name="line.860"></a>
<FONT color="green">861</FONT>      /**<a name="line.861"></a>
<FONT color="green">862</FONT>       * Retrieves the internal English alphabet text message.<a name="line.862"></a>
<FONT color="green">863</FONT>       * <a name="line.863"></a>
<FONT color="green">864</FONT>       * @return The internal English alphabet text message.<a name="line.864"></a>
<FONT color="green">865</FONT>       */<a name="line.865"></a>
<FONT color="green">866</FONT>      public String text()<a name="line.866"></a>
<FONT color="green">867</FONT>      {<a name="line.867"></a>
<FONT color="green">868</FONT>        return _text;<a name="line.868"></a>
<FONT color="green">869</FONT>      }<a name="line.869"></a>
<FONT color="green">870</FONT>    <a name="line.870"></a>
<FONT color="green">871</FONT>      /**<a name="line.871"></a>
<FONT color="green">872</FONT>       * Retrieves the internal English alphabet text message.  Same behavior as <a name="line.872"></a>
<FONT color="green">873</FONT>       * {@link #text()}.<a name="line.873"></a>
<FONT color="green">874</FONT>       * <a name="line.874"></a>
<FONT color="green">875</FONT>       * @return The internal English alphabet text message.<a name="line.875"></a>
<FONT color="green">876</FONT>       */<a name="line.876"></a>
<FONT color="green">877</FONT>      @Override<a name="line.877"></a>
<FONT color="green">878</FONT>      public String toString()<a name="line.878"></a>
<FONT color="green">879</FONT>      {<a name="line.879"></a>
<FONT color="green">880</FONT>        return _text;<a name="line.880"></a>
<FONT color="green">881</FONT>      }<a name="line.881"></a>
<FONT color="green">882</FONT>    }<a name="line.882"></a>




























































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